Sewing machine having a wireless switch and independant controller

ABSTRACT

Sewing machine being transmitted by one wireless switch or more than one transmitted switches being used to transmit one sewing machine or more than one machine simultaneously used. Sewing machines being ramderley transmitted in various start and stop sewing operations by one individual operator and or a group of individual operators using their allocated sewing machines. A rechargeable battery is used. The speed controller is attached to the machine body. The receiver box supplies the voltage to recharge the battery for the transmitter.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a sewing machine and more particularlyto a sewing machine having a wireless switch and a independant operatingspeed controller attached to the machine body of the sewing machine.

There are safety instances when a sewing machine needs to be operated byremote control for example the remote control eliminates the cablebetween the transmission switch and the machine body. A sewing machinewith the above mentioned switch can also be used where a person hasrestricted movement. The transmitter switch may be hand held, placed onthe floor, attached to the arm, leg, wrist, enabling the operator tooguide the material when transmitting. The wireless switch is portable.The independant controller which is attached to the machine body canlimit the operating speed of the machine. This may be done manually.This can also prevent industrial operators sewing to fast and reducingthe quality of the seams. It can also be used whenever serveral sewingmachines work simultaneously, and one single operator can use the remotewireless on/off switch by first selecting the operating motor speed onthe machine body and then activating the wireless switch to start thesewing machine.

2. Description of Related Art

U.S. Pat. No. 4,976,552/1990. Describes a remote control sewing machine,where the connection between the transmitter and the receiver is ensuredby a optical signal. In the techical solution described, the analoguesignal picked up from a variable resistor, which corresponds to thesewing machine foot controller is applied to an analogue digitalconverter, and the numerical signal obtained is modulated by a conveyorwhich connects to an optical transmitter. The receiver obtains, afterdemodulation, a signal with variable amplitude, which controls thesewing machine motor, in this way, by activating the variable resistorof the remote control the motor rotation speed is activated as well.

The solution described above is complicated as it needs a numericalanalogue converter in the command unit, and because it uses light totransmit information, and poses difficulties for the simultaneousoperation of several machines, and therefor this solution has a limitedapplication.

PATENT JP 59 050 792

Tries to overcome this shortcoming and uses radio frequency. In thiscase, the command signal obtained on a variable resistor (whichcorresponds to the sewing machine foot controller) modulates in impulsesa radio frequency conveyor with a rectangular signal whose frequency isdependent on the position of the foot controller; after demodulation,the receiver obtains a rectangular signal which, after having beenamplified, is applied to a tiltable non-stable circuit. The rectangularsignal, which has a variable frequency, is applied to a lower filter,which converts the variable signal of the frequency into a variabletension signal. This signal controls an optic connector, and onceprocessed, the obtained signal controls the rotation of the motor. Thesolution described above allows the operation of several sewing machinesby a single remote control but it is sensitive to interference radiationwhich is generated by the sewing machine motors.

U.S. Pat. No. 5,247,449/1993

Tries to overcome this shortcoming and uses radio frequency. In thiscase, the command signal is picked up from a variable resistor (whichcorresponds to the sewing machine foot controller). An analogue digitalconverter is applied, and then after the frequency modulation(FM) of aradio-frequency signal, the signal is emitted; at reception, afterdemodulation, in a control block, the signal undergoes a reverse digitalanalogue conversion and the variable signal controls the motor rotation.A replacement battery is used. The machine will stop operating when thebattery has reached a certain level of power source to indicate to theoperator that the battery needs to be replaced otherwise the machinewill malfunction by running continually and cannot be stopped and thespeed cannot be changed because the signal cannot be transmitted.

As it uses a radio frequency signal as a conveyor, this technicalsolution allows the operation of several sewing machines by a singleremote control, but it remains complicated: it needs coding and decodingof the information to the signal modulation and demodulation, moreover,even if the frequency modulation (FM) is used to transmit the commandsignal, it is possible that various radio frequency signals—and here wehave the interence signals generated by the sewing machine motor—willoverlap and disturb the useful signal; the use of frequency modulationrequires the use of a relatively wide band, and therefore there is moreinterference with the received signal, even with the use of (additional)coding/decoding operations, it is possible to disturb the receivedsignal, and implicitly the functioning of the sewing machine.

To the replacement battery it is imperative for the operator to see themessage on the machine to prepare for battery replacement otherwise thesafety of the operator may be at risk due to malfunction of sewingmachine and loss of garment production.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a sewing machinehaving a wireless switch and a independant controller attached to themachine body providing a sewing machine substantially free frominterference from a radio wave signal from other transmitters and toprevent the machine malfuction by running continually and cannot bestopped and the machine speed cannot be changed.

It is another object of the present invention to provide a rechargablebattery in a wireless switch so that continuous data to run the sewingmachine and then the machine will stop if the data fails and when therechargable battery runs out of power the machine will not start andanything that breaks the transmission the machine will automatic stop.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a diagram illustrating the following (A) operate LED. (B)power LED. (C) speed control. (D) calibration for the motor. (E)recharging point. (F) Connector to the sewing machine. (G) DIL switchesfor coding. (H) fuse. (J) lid of receiver box. (K) receiver box.

FIG. 2 is a diagram illustrating the following (A) battery charger LED.(B) operate LED. (C) operating switch and spring. (D) rechargeconnector. (E) DIL switches for coding. (F) four springs. (G)transmitter box. (H) lid of transmitter box.

FIG. 3 is a diagram illustrating the following (A) transmitter box. (B)receiver box. (C) view to recharge transmitter box. (D) sewing machineblock.

FIG. 4 is a diagram illustrating the following (A) battery charger LED.(B) the battery recharging position of the transmitter box and receiverbox.

FIG. 5 is a diagram illustrating the following (A) a strap attached totransmitter box. (B) a strap attached to transmitter box providinginsulation for wire. (C) wire along the full lenght of the strap. (D) DCpower rechargable power socket.

FIG. 6 is a diagram illustrating the following (A) the opposite sideview of FIG. 1. (A) IEC inlet mains connection. (B) receiver box. (C)connector to sewing machine. (D) lid of receiver box.

FIG. 7 is a schematic electric circuit of the transmitter.

FIG. 8 is a schematic electric circuit of the receiver.

Their is a strap FIG. 5. (A) attached to the transmitter box thatcontains a insulated wire (C) to reactivate a small amount of signal andtransmits from a restricted location or area when the circuit is mostlyobsured by the body and clothing this ensures that each individualsewing machine of one or more being operated in a confined working areaof a minimum distance of 30 cms apart and 30 cms in front of the sewingmachine from the first sewing machine to the next machine foroperational use and there after to the same distance and frontage apartfor the use in a school classroom, sewing design sample room, garmentfactory, in the home, and any suitable working environment, beingtransmitted by one wireless switch or more than one transmitted switchesbeing activated for one sewing machine or more than one machinessimultaneously used, and sewing machines being ramderley transmitted invarious start and stop sewing operations by one individual operator andor a group of individual operators using allocated sewing machines fortheir sewing requirements, for example stitching the seams of curtains.

Their is for a sewing machine having the use of the micoprocesser. FIG.7 and FIG. 8. That enables to use a dital coded transmission given alarge number of wireless switches the frequency reference of thetransmitter is a single crystal or a saw device and does not requiremultable frequncies mico processer in the transmitter that enables toput out a pseudo-random to avoid interference from adjusted units usingamplitude modulation.

Their is for a sewing machine while being transmitted by the wirelessswitch having a second wireless switch that can be charged on thereceiver box attached to the sewing machine. The second wireless switchis disabled when there is a 5 volt supply present to recharge thebattery. The receiver box supplies 5 volts for the transmitter torecharge. This also avoids a independant power battery charger. Thisprovides continous battery charging while the machine is in useproviding 24 hours of operating use of the machine most useful in agarment factory for continuous production.

The receiver box FIG. 1(B) power LED. The transmitter box FIG. (2) (A)battery charger LED.

Using one transmitter switch and receiver for recharging is unpluggedfrom sewing machine and plugged with the IEC mains supply lead into themains socket.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Now, embodiments of a sewing machine of the present invention will bedescribed in detail hereinbelow with reference to the accompanyingdrawings.

FIG. 7 is a schematic electric circuit of the RC2002 transmitter. A 3.6volt rechargable battery, BT1, powers the transmitter; this can berecharged from the 5 volt input on CN1. The receiver plugs into CN1 andprovides 5 volts DC for this purpose.

R3 AND R4 produce a reference voltage; this is compared with the batteryvoltage, via R1, by the OP-AMP U1. If the battery voltage is less than4V then the output of U1 becomes positive and charges the battery. Thecharging current is limited to about 8 mA by the output restrictionsinherent in the OP-AMP and D1 prevents back leakage from the batterywhen the supply is disconnected. R2 is used to produce a small amount ofhysteresis in the circuit such that the charging stops at about 4.2volts and will not start again until the battery voltage has fallen toabout 3.8 volts. The OP-AMP output is also taken via R6 to switch Q1 andhence illuminates the LED, D2, to indicate when the battery is char ing.

When SW1 is operated power is applied to 1C1 and its associatedcircuitry.

ICI is a hybrid-integrated circuit containing both an integrated RFtransmitter, requiring minimal external components, and an 8-bitmicroprocessor having six IO pins and internal 4 MHz clock generator,when powered up the software in the microprecessor reads a 5-bit codefrom the DIL switch SW2 and generates a pseudo-randomly spaced datastream on GP5 output pin. The data is coded so as to produce one dataword every 2 to 66 ms. Each word consists of six bits; one start bit and5 data bits directly representing the settings of SW2. The start bit isa 300 us pulse and the data bits are 5 width-modulated pulses with acycle length of 900 us and a duty time of either 300 or 600 us.

The random time generator is seeded from the 5-bit code and thus eachtransmitter will produce a different random sequence. This ensures thatthe outputs of more than one transmitter used simultaneously produceonly very limited interference with each other.

The data signal is used to switch the transmitter oscillator on and offthus producing a suppressed carrier amplitude modulation (AM) signal atthe output of the transmitter. The transmitter uses a PCB track as aloop antenna tuned by C4. Frequency reference is provided by a Crystal,XI, this oscillates at 13.56 MHz and is internally multiplied by 32 toproduce a carrier frequency of 433.92 MHz. When recharging power isapplied to the circuit Q2 is switched on via R7 and this in turn pullsthe enable pin of the transmitter to ground disabling the RF output whencharging of the battery is taking place. C5, C6 and R11 form a loopfilter for the RF oscillator and have been selected to give a fairlyfast oscillator start-up time. D3 is powered whenever SW1 is operatedand gives a visual indication of transmitter operation. C1, C2 and C3are supply bypass capacitors.

Continuation of Description of SHAD RC2002 Transmitter:

In addition to the loop antenna on the PCB, an insulated wire isincorporated in the arm strap of the transmitter box. This absorbs someof the radiated signal from the loop and re-radiates the RF signal toenable a better transmission when the circuit is mostly obscured by thebody and clothing.

Description of SHAD RC2002 Receiver

FIG. 8

The live and neutral mains inputs are on CN1 these are taken totransformer TF1 to power the low voltage circuitry and via L1 and L2 tosupply the sewing machine lamp and the phase angle control circuit forthe motor. L1 and L2 provide mains filtering to prevent transient spikesfrom being transmitted back down the mains path in addition the PCBtracks and internal machine wiring are protected by a one-AMP HRC fuse.

Diodes D2 and D4 full-wave rectify the output of TF1 and this issmoothed by C2 to give about 8 volts DC. The 8 volts is then regulatedto 5 volts by the low dropout regulator U2, this is then used to powerthe phase control circuit, microprocessor, radio receiver module and isalso taken to CN3 to provide power to recharge the transmitter. DiodesD1 and D3 produce a full wave rectified signal, which is then taken tothe phase control circuit. R5 provides a signal discharge path and therectified signal is then taken via R4 to the input of a Schmitt TriggerInverter. The Zener Diode D5 is used to clip the signal and provide overvoltage protection to U4C. The output of U4C is a set of positive pulsescoinciding with mains zero crossing, this is then inverted by U4B toprovide a positive going pulse during each mains half cycle, this thencharges C4 via the network of R6, R7 and R8, when the voltage on U4Ainput reaches its positive threshold level then its output switches to alow level. At the end of the pulse D6 is used to quickly discharge C4ready for the next half cycle, by adjusting R8 and R7 the time taken totrigger U4A can be varied and thus the percentage of mains cyclepresented to the motor.

The receiver module M1 is a simple AM detecting receiver with anintergrated data separator to provide a digital output which goespositive when carrier is received. The digital output is taken to amicroprocessor, U3, and this is programmed to decode the incoming datawaveform and compare it with the settings on DIL switch SW1.

Continuation of Description of SHAD RC2002 Receiver:

Once two correct consecutive data words are detected then the RA3 outputis switched high, the incoming data is then monitored and provided thereis a correctly received data word at least every 250 ms then the outputremains high. The signal form RA3 is then taken via R10 to D8, to give avisual indication of data received, and then to the LED positive side ofopto-isolator U1. This produces an AND function with the signal from U4Aand causes the mains side Triac to be triggered while good data is beingreceived.

C1, R1 and R2 form a suppression circuit for the driver Triac in U1, themain Triac; TR1 is used to supply the power to the motor. TR1 is a‘snubber-less’ Triac and reuires no suppression of its own. The phasecontrolled live output from TR1 is taken to CN2 to provide power to themotor in the machine.

R9 and D7 provide an indicator to show when mains power is applied tothe unit. C10 and C5 provide bypass filtering for the 5-volt supply.

1. A sewing machine having a microprocessor controlled switch and amanual motor speed controller provided independently on the machinebody, the sewing machine being provided with a battery powered radiotransmitter to operate the switch remotely and an associated receiver onthe body of the machine, the transmitter using digitally coded signalsto avoid interference with other remotely controlled sewing machines inthe vicinity, the transmitter having a single crystal or saw deviceoscillator and a microprocessor which generates a pseundo-randomlyspaced data stream, the transmitter operating with amplitude modulation,the switch being controlled so as to stop the machine if the stream ofdata is interrupted, the transmitter having a strap for attachment to anoperator, the strap incorporating a wire to help with the propagation ofthe transmitted signal, the transmitter being adapted to be physicallyconnected to a box housing the receiver in order to recharge thetransmitter battery, the transmitter being disabled from operating theswitch while its battery is being recharged.
 2. A sewing machine asclaimed in claim 1 in combination with a second transmitter so that onetransmitter can be used while the other is being recharged.
 3. A sewingmachine according to claim 1 or claim 2 in which a box housing thetransmitter has LEDs to indicate operating and recharging functions andthe box of the receiver has LEDs to indicate power and operation andalso has an IEC mains connector.
 4. A sewing machine substantially asherin described with reference to the drawings.